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On a couple of notes (e.g. Ab4), I'm having a real problem at times getting a good 3/2 string unison. I can get two strings perfect, and then when adjusting the remaining string, I can go past any beat-inducing point, and just before it's perfect I find a really harsh interference is being set up between the strings. Sometimes I can get rid of this by approaching the unison from flat, but that obviously doesn't do wonders in terms of good pin setting.

If I can work out how, I'll try to record this and post it, but is this a problem anyone else recognises?

A) Hammer/String MatingProcedure to Test (Upright)Gently press hammer to string.With other hand, gently press back check against catcher. (This serves to hold the hammer against the strings and open the damper at the same time.)Pluck each string and listen.You should not be able to find a certain pressure on the back check that produces varying tone from each string.I.e. you may be pressing a little hard and hear all strings blocked. But when you reduce the pressure a tiny bit, all strings ring. That is the desired mating result. If you find one string rings, or blocks, while the others don;t, use filing or needling, or string leveling to correct. Note that string leveling will affect damoper seating as well and as such is not the optimal choice for the upright.

B) Unmatched stringsListen to each partial when tuning the unison. Use ghost notes.Try to make a higher partial, like #5 for example, beatless.All lower partials should beat slower than that. I.e. there should be no lower partials beating.If there is, the strings are not matched harmonically. (Unmatched inharmonicity)Measure diameters to confirm different thicknesses.Replace strings with identical diameters, or just mute off offending string for a temporary solution.

C) False beatsListen to each individual string. Each should sound clean.If there are beats, apply gentle preasure to v-bar and string at bridge. If the beating goes away, you have a false beat in that string.

To reduce false beats at the v-bar:

a)Gently tap the string onto the v-bar. (Be careful. The string could break.)

b)Take a screwdriver and slide the string from side to side.You may hear a loud clicking as sthe tring moves in and out of the groove until the groove is burnished.Find a spot on the v-bar to leave the string, so that there is a minimum of false beating.

To reduce false beats at the bridge:

a) Take a brass tap rod or a hammer shank and run it along the string towards the bridge pin. Gently contact the bridge pin. The tapping may seat the string back down onto the bridge. A more aggressive approach is to tap the rod with the rod resting against the string and pin together.

b) Gently tap the bridge pin down. Sometimes strings wear grooves in the side of the pin and humidity fluctuations "pump" the pin out. Tapping brings the pin back down and the groove carries the string with it.

2) The Problem of Stability from Below

It is quite possible to produce a stable tuning from below, due to the "After Tuning" that occurs when you release pressure on the tuning hammer.

"After Tuning" is a term I invented to describe the effect of the Unbending and Untwisting of the tuning pin, on the tension of the Non-Speaking Length (NSL) of the string.

The Tension Band (TB) is a range of NSL tensions that produce stability.

Tuning from below produces a NSL tension at the top of the TB. (Needed to break friction and move the string across the v-bar)

Untwisting (when tuning from below) serves to reduce the tension of the NSL.

If that Untwisting is minimal (old pinblock), then the NSL tension may still be within the TB, and a stable string will be the result.

If the Untwisting is too much and results in flattening of the string on a test blow, simply use the hammer closer to the three o'clock position (on an upright). Now the Unbending will add to the NSL tension and keep the NSL tension from dropping below the TB. (Some situations may result in the Unbending not being enough to counteract the Untwisting. In that case, Controlled Static Massage can work.)

There are numerous other combinations of hammer angle and unbending/untwisting amounts due to pinblock tightness, etc, that can produce stability in any situation.

Also, keep in mind that the length of the NSL determines the amount of the After Tuning on the NSL tension.

Yes yes,Mark but strings rarely are matched even when the same lenght and size, they can come near perfection as on Faziolis, but there is yet some difference between the spectras.

This is something the tuner take in account without (or with) noticing.

for stability,you need a little more tension in front of the pin than in the speaking lenght, with a similar ratio from note to note. tension migrating from the speaking lenght on a hard blow must be counteracted efficiently.

SO the idea of "unstressed pin" mean that at last the pin have the 75Kg of stress coming from the wire, and at best something around 100 kg or a little more

Edited by Olek (11/05/1310:01 AM)

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Thanks Mark/Olek. I'm always impressed with your enthusiasm for helping amateurs like myself. I'd love to be a professional, but here in the UK we don't have any schools any more, and I'm a little too old for an apprenticeship (even if I could find one!)

I'll check the string level and agraffe/bridge contacts. Shouldn't be a major problem with unmatched string inharmonicities -the piano (RX3) is only 2 yrs old and I've only noticed this really in the last 3 or 4 months.

Chris, are you tuning the last string while the other two are unmuted? If so, try muting out the non-reference string so you're only tuning one string against another single string. This is done for some of what Isaac in particular has stated above.

Also, there are times when you get extremely close to having it in tune, but never quite there, and every time you try to take it the rest of the way, it overshoots. At times like these, you just have to back it off a ways and re-approach the tuning of that string.

I suggest trying these before you go taking a bunch of measurements, etc.

Chris, are you tuning the last string while the other two are unmuted? If so, try muting out the non-reference string so you're only tuning one string against another single string. This is done for some of what Isaac in particular has stated above.

Also, there are times when you get extremely close to having it in tune, but never quite there, and every time you try to take it the rest of the way, it overshoots. At times like these, you just have to back it off a ways and re-approach the tuning of that string.

I suggest trying these before you go taking a bunch of measurements, etc.

Thanks , TenorJim (I watched westerns),

The strongest is to use the central string for reference and tune the 2 others the same so they are coupling "above" the central one.

Acoustically it is strong so it hide better defects.

It can help. Yes ghosting, or focusing on the partials allow to hear where the moaning comes from, if it comes from hammer mating it will be present always.

PS you also can focus on the fundamental and tune it strong, then it tend to "absorb" partials (there are less, the tone seem to "eat" itself) makes a sort of closed tone that moan when played strong (because partials create that above a certain force)

Not very elegant tone

Edited by Olek (11/05/1301:14 PM)

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It is critical that you call your Senators and Representatives and ask them to cosponsor S. 2587 and H.R. 5052. Getting your legislators to cosponsor these bills

There is a limit beyond which unmatched iH produce unacceptable results. Below is not a problem. (Subjective, of course, but the limit still exists.)

Obviously if there is not enough friction at Vbar agrafes or capo you cannot obtain that higher tension (due to the pin, not the speaking lenght)

That differential I learned some 20 years ago from a concert tuner. That is the basis for concert setting but for stability at large.

Once obtained it takes a very long time for the note to be out of tune it is sort of auto balanced setup, using the energy stored in the pin (and pinblock, but the pin is more predicteable probably) to maintain the tension balance between pin and upper segment of wire.

I hope I am not divulging a secret.

Add that if a string rise it is considered as more unnoticeable than the opposite , so all of that goes in a similar direction (tuning "high".)

It makes a difference to the tuner, when he begin to learn to focus on a so small length of steel as the pin and the upper wire segments, while he was used to focus on the speaking length before then.

Fazioli call that "tuning the front duplex" but I am unsure it makes sense, acoustically.

Edited by Olek (11/05/1301:22 PM)

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It is critical that you call your Senators and Representatives and ask them to cosponsor S. 2587 and H.R. 5052. Getting your legislators to cosponsor these bills

More comfortable for me is to include the string on both sides of the front terminating point as an important part of my tuning focus. The quality of the front terminations is often in the hands of the tuner.

The normal force is a normal vector which is a function of the string tension (approx. 150lbs +/- 20?) which is uniform in any one section, and the angles of the string bending at the pressure points. Do these vary that much?

Now, consider this:

You are trying to raise pitch. You turn the pin, and the pitch does not change. Do you assume high friction at the bearing points, or do you notice that the non speaking length is quite long, and therefore the tension in the non speaking length is not rising as fast as if the non speaking length was shorter, due to the elasticity of the string?

Because they both could be the reason, except that I do not find reason enough to assume much variation in friction from one pin to the next in the same section of the piano. But I do notice a heck of a difference in the non speaking length, and hence, a large difference in how the pitch responds to the hammer.

IMHO there should always be enough friction to leave non speaking length tension on the high side of the tension band.

Try using the Controlled Static Massage I spoke about. Works everytime for me.

I see what you mean Mark, I have been using the bowing of the pin for years, to create that raised frictiion.

Now when tuning, I work so the wire reacts as a whole, that mean I learn the amount of difference before I have access to the speaking length then wait for the tension to be similar on both sides and tune from there. the slightest motion on the pin change the tone in the speaking length (mostly because I raised the tension a lot, the wire behave more directly, that is when possible, there are always pianos with too much friction)

Then I "tune" the pin and not the wire, really, I have learned how much extra tension is in the front segment at the moment I perceive the pin begin to move at its bottom - I want that to be late, as it allows to have much more energy stored in the wire and the pin, that make them more reactive - my ears know what do I want in terms of pitch, so it is as if I was tuning an interval, as I tune the bottom of the pin in position while the string is way out of tune, really too high.

I also learned the delay due to friction and the stretch of the wire, but on most pianos it can be as on verticals, a very direct sensation.

That sensation contains :A small part in front of the pin eventually overtense and about to move (difficult cases) the tension in the free section of wire before the bearing pointthe tension in the speaking length

I have to know when to stop to rise but that is mostly the bottom of the pin that dictates that.

When I place the bottom in the wanted position I must be aware of all the differences in stretch and tension in the 3 parts of the wire, but frankly I am under the impression I work with a rigid rod and not something highly elastic (that is due to the stiffening obtained with the extra tension may be).

When working slow enough that is what the sensations are.

Then I backup my pin to neutral, the wire must follow, I go a little past the equilibrium point (twisting the pin the other side without having it moving at its bottom- mean sometime "braking" with some pressure) and release.

AT release the pin twist back a little and the note is set.I have to read the pin correctly and to read the wire and friction too.

I learned first to install the extra tension by a little bowing of the pin indeed, and it push the tuner to use force , bowing the pin while turning, and I do not like it too much (you maintain your tension reserve by bowed posture of the pin)

One can also go to neutral, if he is used to do so, and then add a little tension by gently pushing the lever up.

That ratio of tension between speaking length and upper segment is unavoidable, with different explanations, resistance to heavy blow, reserve so if the string deforms a little the pitch will not lower as much.

It is basically as a knot . One have to provide some activity, some energy, to "fight" the one that will come from the string when the piano plays.

Even without the tension passing the bearing point there are impact waves that do.

It also influences the tone because it is a different type of fixture than something more "neutral".

Now of course if we go by the different types of pinblocks frictions under the upper segment and at the bearing point, we are with different categories and different tactics may apply, lever orientation, etc.

Something remain unchanged when the pin is set, it is an energy reserve, a loaded spring. It even helps for old blocks, but cannot be really done finely on extra tight pins where you can only manage the pin up to a certain point .

Yes some pianos reacts after some time so they are difficult to set with the way described. Then I minimize the overstretch of course. I could play the note repeatedly until the tension is balanced between the upper segment and speaking length but it would be too long.

When I feel that the upper segment is about to raise more the speaking length because it stretch I must be in position to twist back the pin clockwise.

That is what I do, judging at what point my note will be in tune and the pin in the same position than when I begin.

Leaving that active "knot" last very long, it is not rare on the next tuning to have no necessity to turn many pins, the extra tension at some point raised a little the pitch, or the pin is yet tense and in the same position I left it but the wire have deformed a little and lost some tension.

In that case I have to work the pin in its tense position and move it only a very little but as a whole. Release, done. Next tunings are faster once all pins are set.

I probably do not describe that very accurately, it is a good idea to use concepts and terminology, but not too much, as at some point it get useless. There are 4 types of situations well described in the Ken Burton's book.

Klaus Fenner did the same with more parameters and finally proposed 28 different situations and how to deal with each one !

Best regards

Obviously

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and yes of course the last thin things are done by "massaging" , but the bottom must be firm first.

The bearing points are rarely a problem that is may be what I mean by "working with direct feel of the wire as a whole.

The reaction differs from pin to pin, but I experience way less differences in time due to the difference in lenght of wire with the "knot" well balanced.

I believe I leave a similar energy reserve from pin to pin, I have to analyse that more precisely to see if this is different with short, vs long front segment. all is done with feeling and sensations, possibly I do stability and do not really realize how.

_________________________
It is critical that you call your Senators and Representatives and ask them to cosponsor S. 2587 and H.R. 5052. Getting your legislators to cosponsor these bills

C) False beatsListen to each individual string. Each should sound clean.If there are beats, apply gentle preasure to v-bar and string at bridge. If the beating goes away, you have a false beat in that string.

To reduce false beats at the v-bar:

a)Gently tap the string onto the v-bar. (Be careful. The string could break.)

b)Take a screwdriver and slide the string from side to side.You may hear a loud clicking as sthe tring moves in and out of the groove until the groove is burnished.Find a spot on the v-bar to leave the string, so that there is a minimum of false beating.

To reduce false beats at the bridge:

a) Take a brass tap rod or a hammer shank and run it along the string towards the bridge pin. Gently contact the bridge pin. The tapping may seat the string back down onto the bridge. A more aggressive approach is to tap the rod with the rod resting against the string and pin together.

b) Gently tap the bridge pin down. Sometimes strings wear grooves in the side of the pin and humidity fluctuations "pump" the pin out. Tapping brings the pin back down and the groove carries the string with it.

I tried this. My piano has had such an annoying false beat at C#5 that made me transpose A major pieces to Ab major; a good skill to acquire, but still...

C) False beatsListen to each individual string. Each should sound clean.If there are beats, apply gentle preasure to v-bar and string at bridge. If the beating goes away, you have a false beat in that string.

To reduce false beats at the v-bar:

a)Gently tap the string onto the v-bar. (Be careful. The string could break.)

b)Take a screwdriver and slide the string from side to side.You may hear a loud clicking as sthe tring moves in and out of the groove until the groove is burnished.Find a spot on the v-bar to leave the string, so that there is a minimum of false beating.

To reduce false beats at the bridge:

a) Take a brass tap rod or a hammer shank and run it along the string towards the bridge pin. Gently contact the bridge pin. The tapping may seat the string back down onto the bridge. A more aggressive approach is to tap the rod with the rod resting against the string and pin together.

b) Gently tap the bridge pin down. Sometimes strings wear grooves in the side of the pin and humidity fluctuations "pump" the pin out. Tapping brings the pin back down and the groove carries the string with it.

I tried this. My piano has had such an annoying false beat at C#5 that made me transpose A major pieces to Ab major; a good skill to acquire, but still...

Anyways your procedure completely fixed it.

Thanks!!

Kees

You're welcome Kees. Nice to hear from you again.(I've been way too busy to read your article. Sorry. Will get to it eventually)

More comfortable for me is to include the string on both sides of the front terminating point as an important part of my tuning focus. The quality of the front terminations is often in the hands of the tuner.

yes I see what you mean, if you add pin's position to that you have a complete picture.

In that sense , some pianos do not allow much control on pin posture. because the friction with underfelt is higher than the torque, or because the torque is so high that the bottom position of the pin is difficult to set and does not make much of a difference at that point, as very high torque mqke the pin more rigid.

On lower torque, the added pin rigidity (and springiness) reinforce and clean the tone to the point I can notice the firmness of pin setting if I listen to the tone (more the lack of firmness, but it can be noticed)even on youtube or mp, it is not a so discrete component of tone.

I will blind test that the day a colleague agree to do the testing.

Edited by Olek (11/08/1304:16 AM)

_________________________
It is critical that you call your Senators and Representatives and ask them to cosponsor S. 2587 and H.R. 5052. Getting your legislators to cosponsor these bills